Rail road car with cantilevered articulation

ABSTRACT

An articulated rail car has a plurality of rail car units joined together at articulation connections, and carried upon a number of rail car trucks that is equal to the number of rail car units plus one. At least one of the articulated connectors is located at an offset distance from the nearest rail car truck, such that the adjacent rail car has an overhang, or cantilever, between the center of the truck and the pivot center of the articulation. The truck is a two axle, four-wheel freely pivoting truck.

This application is a continuation of U.S. patent application Ser. No.10/081,120 filed Feb. 22, 2002, now U.S. Pat. No. 7,047,889, which is acontinuation of U.S. patent application Ser. No. 09/614,815 filed Jul.12, 2000, now abandoned.

FIELD OF THE INVENTION

This invention relates generally to articulated rail road cars.

BACKGROUND OF THE INVENTION

The dimensions of rail road cars are constrained by a number ofgeometric considerations. First, on tangent track (that is, straighttrack) a rail road car can not be too wide, otherwise it may foul thesides of bridges, tunnels, roadside fittings such as switches orsignals, or other cars of the same size passing on an adjacent track.Similarly, rail cars cannot be taller than the minimum regulated heightsof the lowest bridges or tunnels on the tracks along which it is totravel. Third, the weight a car can carry is limited by the capacity ofthe tracks, rails and road bed over which it is to travel.

With reference to FIGS. 1 a, 1 b, 1 d and 1 e, on curved track, therelationship between length and width is important. Traditionally,single unit rail road cars A20 have had a car body supported by a railcar truck A22, A24 at either end. The mounting to a standard two axle,four wheel truck is at a pivot at the truck center, A26. The cars areconnected at a releasable coupler A28 in the commonly known manner. Whensuch a car passes through a curve trucks A22, A24 follow the arcindicated by the track centerline, S₁, while the car body centerlinebetween the truck centers forms a chord κ of the arc. Chord κ subtendsan angle α₁ of arc S₁. This is shown, with exaggerated proportions, inFIG. 1 a. The track center line radius is indicated as R₁. At midspanbetween the trucks, the inside edge of the car follows a circular archaving a radius of curvature indicated as the limiting inside minimumradius R₂. Car A20 is shown as having overhanging end portions A30 andA32 that extend longitudinally outboard of the respective truck centers.As car A20 passes through a curve the extreme outside corners of endportions A30 and A32 will follow along an outer radius, namely thelimiting minimum outside radius indicated as R₃.

For any curve, the longitudinal center line of the car, CL, at mid-spanbetween the trucks will lie some distance, δ, inward from the center ofthe track, as indicated by δ₁. This distance δ depends on the radius ofcurvature, R₁ of the tracks, and the distance between truck centers, L₁.As shown in FIG. 1 a, for a given dimension L₁, δ increases as theradius of curvature decreases, as indicated by R₄. Alternatively, for afixed track radius R₁, as the truck center distance L₁ increases, δ alsoincreases. The left hand example of FIG. 1 a demonstrates this. For atrack having a radius of curvature R₄, the arc is identified as S₂.Placing two of rail road cars A20 on this track, the chord lengthremains κ but the subtended angle, α₂, is larger than α₁, and thedistances between the inner and outer clearance radii, R₅ and R₆, isgreater than between R₂ and R₃, with a consequent increase in δ form δ₁to δ₂.

In North American service, the relationship of rail road car width andlength, and the corresponding necessary reductions in width required astruck center distance increases are set out by the American Associationof Railroads (AAR) in various AAR standards. Cars to be used ininterchangeable service are required to conform to the AAR standards.For all cars, including AAR plate ‘C’ cars, the limiting centerlinetrack radius, R1, is a standard minimum dimension of 5300.375 inches.For plate ‘C’ cars, the limiting minimum inside radius, R₂, isdetermined on the basis of a car (“the base car”) having a truck centerspacing of 46′-3″ (555 inches), and a maximum car width of 10′-8″ (128inches). For this standard car, δ₁ is roughly 7.25 inches, so R₂ isroughly 5229.12 inches. For plate ‘C’ cars the limiting minimum outsideradius, R₃, is defined as being greater than R₁ by the same amount as R₂is less than R₁. Thus, adding the 7.25 inch offset, plus half of the carwidth, namely 64 inches, gives an R₃ of 5371.63 inches.

If car A20 is not to foul adjacent cars or adjacent structures whilepassing through curves, as the truck center length increases beyond46′-3″, the width of the car must decrease correspondingly so the insideof the car at mid-span between the trucks of the car does not cut to theinside of R₂. The allowable width of a car for a given truck centerdistance can be calculated from this datum case. A different standardapplies for auto-rack rail road cars, but the principles are the same.In AAR specification M-950-A-99, the maximum width of a bi-levelauto-rack car having a length of 90′ over the strikers is given as 119″at mid span, and 121″ at the strikers. Typically such an auto-rack hastruck centers on either 64′ or 66′ spacing. The limiting minimum insideradius, R₂, for this car is 5226.06 inches and the limiting minimumoutside radius, R₃, is 5373.27″. The outside extreme corners A30, A32must stay within R₃. In some cases, for long overhangs, the ends of thecar must be narrowed.

Similarly, some types of inter-modal well cars are used for carryingcontainers, or for carrying highway trailers or a combination of thetwo. The well must be wide enough to accommodate either the highwaytrailers or the containers, as may be required. Center beam cars, suchas are commonly used for carrying stacked bundles of lumber must havewide enough bunks to carry standard widths of bundles.

Auto-rack rail road cars must be wide enough not only to carryautomobiles, but they also must be wide enough to allow space forpersons loading and unloading the automobiles to open the automobiledoors and get in and out of the automobiles. The person loading theautomobiles must also have sufficient space to walk beside theautomobiles. When the clearance allowed is too small, the loadingpersonnel may inadvertently damage the finish of the automobiles, givingrise to damage claims. Alternatively, it may be that it is helpful, ornecessary, to allow a clearance envelope to accommodate motion of thelading during travel. In each case, it is helpful to lengthen the car toincrease lading, but such lengthening is limited by the need to maintaina car body width.

Conventionally, articulated rail road cars have two or more rail carunits permanently connected to each other such that one rail car truckis shared between two adjoining rail car units. Typically, anarticulated rail road car having a number of rail car units ‘n’ issupported on ‘n+1’ trucks. An articulation connection is a permanentconnection unlike a hitch or standard releasable coupling that can becoupled and uncoupled each time a new train consist is made up in ashunting yard. By contrast, an articulated connector, once assembled,tends only to be taken apart during repair or replacement at a workshop,and is considered a permanent connection.

In FIG. 1 b, an articulated rail road car B20 has first and second railcar units B22 and B24. They are joined at their respective inboard endsB26 and B28 by an articulation connection B30 mounted directly above thetruck center of a four wheel truck B32 that is shared between units B22and B24. The track radius is shown as R₁. The allowable inside radius isshown as R₂. The allowable outside radius is shown as R₃. The extremecorners of outboard ends B34 and B36 fall just within radius R₃. Whenarticulated truck B32 is used, while the inside of the body of car B20is tangent to radius R₂, there is clearance between the outermostextremities of inboard ends B26 and B28. This occurs because truck B32,is constrained to follow the tracks, and there is no overhang of eitherunit B22 or unit B24 at truck B32 comparable to the overhang at each ofthe outboard ends B34 and B36.

Further, in the example of FIG. 1 b, a vertically downward shear load ispassed from each of car units B22 and B24 into articulation connectionB30, and then directly into the truck bolster of truck B32. That is,each of the car units B22 and B24 approximates a span having a simplesupport at each end into which the vertical shear load, but no bendingmoment, is passed for reaction through the trucks, and ultimately, bythe road bed lying underneath the rails. It will be appreciated that ina multi-unit articulated car having three or more car units, at leastone unit will have an articulation connection under both ends.

FIG. 1 d shows a three-unit articulated rail road car C20, having amiddle rail car unit C22 and end rail car units C24 and C26. As in FIG.1 b, rail road car C20 is shown on a section of track having centerlineradius R1, minimum inside clearance radius R₂, and minimum outsideclearance radius R₃. As before, the truck center distance is L₁, and themid-span lateral inset of the longitudinal centerline of rail car unitC22 (and, in this example, also of rail car units C24 and C26), is againδ₁. As above, car unit C22 is joined to car units C24 and C26 byrespective articulated connectors C28 and C30 whose points ofarticulation lie directly above corresponding shared trucks C32 and C34.It can be seen that the outside corners C36 and C38 of car unit C22, andcorners C40 and C42 of car units C24 and C26 lie well inward of outsideradius R₃.

The rail road cars shown in FIGS. 1 a, 1 b and 1 d have pivoting, twoaxle, four-wheel trucks that pivot relative the longitudinal centerlinesof the respective car bodies. This permits the truck to run along thearc while the car body forms a chord of the arc, the chord meeting thetrack centerline at an angle. Single truck railcars are known,particularly in light-weight service as for passenger car train setswhere the individual axle loading levels tend to be low relative to thecustomary load limits of freight cars. The use of single axle trucks inan articulated freight car may tend to be disadvantageous. First, asingle axle truck is generally fixed relative to the car body. Ifallowed to pivot freely in the manner of a double axle truck, a singleaxle truck would not necessarily continue to follow the rails. However,as car length increases, fixed orientation single axle trucks face anincreasing angle of attack relative to the rails when running through acurve. Consequently, single axle trucks tend not to be recommended forrail cars having a separation of more than about 39 feet between trucks.However, the issue of having to reduce the width of the rail road caroccurs when the truck centers are already more than 46 ft. 3 in. apart.Second, a single axle truck cannot, in general, carry the same load as adouble axle truck having comparable wheels. While single axle trucks maybe suitable for the carriage of short, light passenger cars, the lengthand greater lading of freight cars tends to require double axle trucks.

As noted, in the arrangement shown in FIG. 1 b, the articulated rail carunits are able to pivot relative to the shared truck, and relative toeach other. There is a permanent articulated connector, having a malemember and female socket. The articulated connector has a pivot axisthat is generally located directly above the center of the shared truck,such that the pivot point of the socket is coincident with the truckcenter when viewed from above. In this type of arrangement, the pivotpoint tends always to lie directly above the centerline of the track.One type of articulated connector is shown in U.S. Pat. No. 4,336,758 ofRadwill, issued Jun. 29, 1982, in which the main pin is nominallyvertical. Another type of articulation connection is shown in U.S. Pat.No. 5,271,511 of Daugherty, Jr., issued Dec. 21, 1993 in which a mainpin, in the nature of a removable shaft, is nominally horizontal.

One advantage of articulated connections is that they tend to take upless longitudinal space than common interchangeable couplers. In oneapplication, a number of large automobile manufacturing facilities havea loading siding length that is chosen to handle a string of cars,whether articulated or otherwise, or some combination thereof, up to alimit of 500 ft. in length. One automobile manufacturer would like to beable to load 4 automobiles of a type having a length of 239″ (or less),or five compact automobiles on a single auto rack car, or, in the caseof an articulated car, on a single car unit. When standard releasablecouplers are used on stand alone cars, a 500 ft siding can accommodate 5rail cars with an overall length of roughly 470′, with a total capacityon a single deck level of 20 automobiles of 239 inch length each. A pairof three-pack articulated rail road cars made according to the presentinvention may tend to permit a six unit rail road car to be accommodatedon a 500 ft siding with a total capacity on a single deck level of 24automobiles of 239 inch length each.

Another advantage is that articulated couplers tend to be slacklesscouplers. This tends to reduce the longitudinal shock load transmittedduring run-in and run-out, and during shunting. Other types of slacklesscoupling exist other than articulated couplings. For example, it ispossible to use a draw bar between cars, as shown, for example, in U.S.Pat. No. 4,929,132 of Yeates et al., issued May 29, 1990.

A draw bar is a bar of fixed length that is connected at pivot points ateither end to adjacent rail car units on either side. A draw bar reducesthe clearance required between the car units as compared to releasablecouplers, but cannot be used to transmit a shear load. That is, it maynot tend to be advantageous to try to pass a vertical shear load througha draw bar. Thus use of a draw bar rather than an articulated connectorgenerally requires that there be an adjacent truck mounted to each ofthe rail car units, with the consequent increase in weight, length,maintenance, and expense.

SUMMARY OF THE INVENTION

In an aspect of the invention there is an articulated rail road freightcar having first and second rail car units connected at a cantileveredarticulation.

In an additional feature of that aspect of the invention, each of thefirst and second rail car units has at least one deck upon whichvehicles can be loaded. In another additional feature, the freight carhas at least one member mounted to permit vehicles to be conductedbetween said first and second rail car units. In another additionalfeature, the freight car is an auto rack car having bridge platesmounted to permit automobiles to be conducted between rail car units. Inanother feature, the freight car is a three pack rail road car having atwo truck middle unit and a pair of single truck end units.

In another aspect of the invention, there is an articulated rail roadcar having a plurality of rail car unit bodies carried on a plurality ofrail car trucks, the rolling direction of the rail road car defining alongitudinal direction, the plurality of rail car bodies including afirst rail car unit body and a second rail car unit body connectedtogether at an articulation connection, the rail car trucks including afirst rail car truck located closer to the articulation connection thanany other, the first rail car truck being pivotally mounted to the firstrail car body, and the articulation connection being eccentricallymounted relative to the first truck. In an additional feature of thataspect of the invention, the truck is a two axle truck mounted to pivotabout a vertical truck center axis relative to the first car body, andthe articulation connection is cantilevered longitudinally relative tothe truck center.

In another aspect of the invention, there is an articulated rail roadcar, the car having a rolling direction defining a longitudinaldirection on tangent track. The rail road car has first and second railcar units, and a plurality of rail car trucks upon which the railroadcar is carried. The first and second rail car units are connected at anarticulation connection. One of the rail car trucks is closest to thearticulation connection, the closest rail car truck being mounted to thefirst rail car unit, and the articulation connection is mountedlongitudinally eccentrically relative to the closest rail car truck.

In an additional feature of that aspect, the closest rail car truck is atwo axle truck. In another additional feature, the first rail car unithas a body, and the closest rail car truck is mounted to pivot about avertical truck center axis relative to the body of the first rail carunit. In another additional feature, the articulated connection has afirst portion mounted to the first rail car unit, and a mating secondportion mounted to the second rail car unit, the first and secondportions meeting on a bearing interface defining a portion of aspherical surface. In still another additional feature, the articulationconnection has a first portion rigidly mounted to the first rail carunit, and a mating second portion mounted to the second rail car unit,the articulation connection being capable of transferring a verticalshear load from the second portion to the first portion.

In another aspect of the invention, there is an articulated rail roadcar, the rail road car having a rolling direction on tangent trackdefining a longitudinal direction. The articulated rail road carincludes first and second rail car units joined at an articulatedconnection. The first rail car unit has a first end proximate to thearticulated connection, and a second end distant from the articulatedconnection. The first car unit has a first rail car truck pivotallymounted thereunder. The first rail car truck is located closer to thefirst end of the first rail car unit than to the second end of the firstrail car unit, and the articulated connection is longitudinallyeccentric relative to the first rail car truck.

In an additional feature of that aspect of the invention, the secondrail car unit has a first end proximate to the articulated connection,and a second end distant from the articulated connection. The secondrail car unit has a second rail car truck mounted thereunder. The secondrail car truck is located closer to the second end of the second railcar unit than to the first end of the second rail car unit, and thesecond rail car unit is free of rail car trucks between the articulationconnection and the second rail car truck. In a further additionalfeature, the articulation connection is a first articulation connection,and the rail road car has a third rail car unit joined to the secondrail car unit at a second articulation connection.

In a further feature, the second articulation connection is mountedeccentrically relative to the second rail car truck. In still anotheradditional feature, one articulation connection is a first articulationconnection. The rail road car has a third rail car unit joined to thesecond rail car unit at a second articulation connection. The third railcar unit has a first end proximate to the second articulated connection,and a second end distant from the second articulated connection. Thethird car unit has a second rail car truck mounted thereunder, thesecond rail car truck being located closer to the first end of the thirdrail car unit than to the second end of the third rail car unit, and thesecond articulated connection is longitudinally eccentric relative tothe second rail car truck.

In another additional feature, the rail road car is free of trucksbetween the first articulation connection and the second articulationconnection. In still another feature the rail road car is free of trucksbetween the first and second trucks. In a further feature, the firstrail car unit is supported by a second rail car truck, and the secondrail car truck is located closer to the second end of the first rail carunit than to the second end of the first rail car unit. In still anotherfeature, the articulation connection is a first articulation connection,and the rail road car includes a third rail car unit joined to thesecond end of the first rail car unit at a second articulationconnection. In a still further feature, the second rail car truck ismounted underneath the first rail car unit, and the second articulationconnection is longitudinally eccentrically located relative to thesecond rail car truck. In yet another additional feature, the first carunit is the middle car unit of a three unit pack. In another additionalfeature, the second and third rail car units each have a near endproximate to the first car unit, and a far end distant from the firstcar unit, and each of the second and third car units is supported by arespective rail car truck mounted closer to the far end than to the nearend thereof.

In an additional feature of the invention, the rail car truck has afirst pair of wheels mounted on a first axle, and a second pair ofwheels mounted on a second axle. The first axle is longitudinallyoutboard relative to the second axle, and the articulation connection islongitudinally outboard relative to the first axle. In anotheradditional feature, the first car unit has side bearing arms extendingfrom the first end thereof toward the second car unit, and the secondcar unit has side bearing arms extending therefrom to engage the sidebearing arms of the first car unit. In a farther additional feature theside bearing arms of the first car unit have bearing surfaces facingupward, and the side bearing arms of the second car unit have bearingsurfaces facing downward.

In another additional feature the first car unit has a main bolstermounted over the first truck, and a center sill extending longitudinallyoutboard therefrom. The center sill has a distal end longitudinallydistant from the main bolster, and the articulation connection ismounted to the distal end of the center sill. In still another feature,the center sill is a stub sill. In a further additional feature, firstrail car unit has a well intermediate the first and second ends thereof.

In an alternate additional feature, the first unit has a main bolstermounted above the first truck, a center sill extending longitudinallyoutboard of the first truck toward the second rail car unit. An endmostlateral structural member, (whether an end bolster or and end sill),extends transversely relative to the center sill, the endmost lateralstructural member being located longitudinally outboard of the mainbolster, and the center sill has a distal end outboard of the endmostlateral structural member to which the articulation connection ismounted. In an additional feature, the first car unit has longitudinallyextending members located transversely outboard and to either side ofthe center sill. The longitudinally extending members run between themain bolster and the endmost lateral structural member. Thelongitudinally extending members extend longitudinally beyond theendmost lateral structural member to define a first pair of side bearingarms. The second car unit has a second pair of side bearing arms mountedthereto, located to engage the first pair of side bearing arms.

In another additional feature, the first car unit has longitudinallyextending side sills connected to the main bolster and the end bolster.The first car unit has longitudinally extending members each locatedintermediate the center sill and a respective one of the side sills. Thelongitudinally extending members run between the main bolster and theend bolster. The longitudinally extending members extend longitudinallyoutboard beyond the end bolster to define a first pair of side bearingarms; and the second car unit has a second pair of side bearing armsmounted thereto, located to engage the first pair of side bearing arms.

In another aspect of the invention there is an articulated rail road carhaving first and second rail car units joined at an articulationconnection. The first rail car unit has a first end proximate thearticulation connection and a second end distant from the articulationconnection. The first rail car unit is mounted upon a pair of first andsecond rail car trucks located under the first and second ends of thefirst rail car unit respectively and being pivotable relative theretoabout truck center axes. The first rail car unit has a pair of first andsecond main bolsters located at either end thereof, the main bolstersbeing mounted over the first and second rail car trucks respectively.The rail car has structure connected to maintain the main bolsters inposition relative to each other. The first rail car unit has a centersill extending outboard of the first main bolster toward the second railcar unit, the center sill having an outboard end. The articulationconnection is mounted to the outboard end of the center sill.

In an additional feature of that aspect of the invention, the secondrail car unit has a first end proximate the articulation connection anda second end distant from the articulation connection. The second railcar unit is mounted upon a third rail car truck located under the secondend of the second rail car unit, and the second rail car unit is free oftrucks between the third rail car truck and the articulation connection.In an additional feature of that additional feature, the articulatedconnection is a first articulation connection. The rail road car has athird rail car unit connected to the second rail car unit at a secondarticulation connection. The second rail car unit has a main bolstermounted above the third rail car truck. The second rail car unit has acenter sill extending outboard of the third rail car truck toward thethird rail car unit. The center sill of the second rail car truck havinga distal end distant from the third truck, and the second articulationconnection is mounted to the distal end of the center sill of the secondrail car unit.

In another additional feature, the third rail car unit has a first endproximate the second articulation connection and a second end distantfrom the second articulation connection. The third rail car unit ismounted upon a fourth rail car truck located under the second end of thethird rail car unit, and the third rail car unit is free of trucksbetween the fourth rail car truck and the second articulationconnection.

In another additional feature, the articulation connection is a firstarticulation connection, the outboard end of the center sill is a firstend thereof, and the rail road car has a third rail car unit connectedto the second end of the first rail car unit at a second articulationconnection. In still another additional feature, the center sill is athrough center sill having a second end located outboard of the secondmain bolster, and the second articulation connection is mounted to thesecond end of the center sill.

In a still further additional feature, the third rail car unit has afirst end proximate the second articulation connection and a second enddistant from the second articulation connection. The third rail car unitis mounted upon a fourth rail car truck located under the second end ofthe third rail car unit, and the third rail car unit is free of trucksbetween the fourth rail car truck and the second articulationconnection.

In another aspect of the invention, there is an articulated rail roadcar having a number of rail car units. The units include at least afirst rail car unit, a second rail car unit, and a third rail car unit,the second rail car unit lying between the first and third rail carunits. The articulated rail road car has a number of rail car trucksmounted to support the rail car units, the number of rail car trucksbeing equal to the number of rail car units plus one. The first rail carunit is connected to the second rail car unit at a first articulationconnection. The second rail car unit is connected to the third rail carunit at a second articulation connection. None of the rail car trucks ismounted centrally under either of the first and second articulationconnections.

In an additional feature of that aspect of the invention, the rail roadcar is free of trucks between the first and second articulationconnections. In a further feature, each of the first and second rail carunits is supported by a spaced apart pair of the rail car trucks mountedthereunder. In a still further feature, each of the first and third railcar units has a cantilever member extending toward the second rail carunit, and the first and second articulation connections are mountedrespectively to the cantilever members of the first and third rail carunits. In a still further feature, a fourth rail car unit is connectedto the third rail car unit at a third articulated connection. The thirdrail car unit has a first end adjacent the second articulationconnection and a second end adjacent the third articulation connection.The first rail car unit is supported by a pair of the rail car trucks,namely first and second spaced apart rail car trucks mounted thereunder.A third one of the rail car trucks is mounted under the first end of thethird rail car unit. In still another feature, a fourth rail car unit isconnected to the first rail car unit at a third articulated connection.A fifth rail car unit is connected to the third rail car unit at afourth articulated connection. The first rail car unit has a first endadjacent the first articulation connection and a second end adjacent thethird articulation connection. The third rail car unit has a first endadjacent the second articulation connection and a second end adjacentthe fourth articulation connection. A first of the rail car trucks ismounted under the first end of the first rail car unit. A second of therail car trucks is mounted under the first end of the third rail carunit.

In a still further aspect of the invention, there is an articulated railroad car wherein, when standing on tangent track, the rail road car hasa first rail car unit and a second rail car unit. The first and secondrail car units are joined at an articulated connection. Each of thefirst and second rail car units has a proximal end near the articulatedconnection, and a distal end lying far from the articulated connection.The distal end of the first rail car unit is supported by a first railcar truck. The distal end of the second rail car unit is supported by asecond rail car truck. A third rail car truck is mounted to the railroad car between the first and second trucks. The rail road car is freeof trucks between the first and second trucks other than the thirdtruck. The third truck is spaced from the first truck a first distance,D₁. The articulation connection is spaced from the first truck a seconddistance, D₂. The first distance, D₁, is less than the second distance,D₂.

In an additional feature of that aspect of the invention, the thirdtruck is spaced from the second truck a third distance, D₃, and D₃ isdifferent from D₁. In a further feature, D₃ is greater than D₁. In analternative feature, the third truck is spaced from the articulatedconnection a third distance, D₃. The second truck is spaced from thearticulated connection a fourth distance, D₄, and D₄ is greater than D₃.In a further feature, the third rail car truck is pivotally mounted tothe first rail car unit and the first distance, D₁; is greater than 46ft.-3 in.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a shows a conceptual top view of two rail road cars on curvedtracks;

FIG. 1 b shows a conventional two-unit articulated rail road car on acurved track;

FIG. 1 c shows a conceptual top view of a two unit articulated rail roadcar according to the present invention, on a curved track;

FIG. 1 d shows a conventional three-unit articulated rail road car on acurved track;

FIG. 1 e shows a three unit articulated rail road car, an alternative tothe two-unit articulated rail road car of FIG. 1 c, on curved track;

FIG. 1 f is a comparison view of the three unit articulated rail roadcars of FIGS. 1 d and 1 e;

FIG. 1 g is a conceptual view of a part of the rail road car of FIG. 1d;

FIG. 1 h is a further conceptual view of the rail road car of FIG. 1 d;

FIG. 2 a shows a side view of the two unit articulated rail road car ofFIG. 1 c as on straight track;

FIG. 2 b shows a top view of the rail road car of FIG. 1 c as onstraight track;

FIG. 2 c shows a cross-section of an illustrative articulated connectorsuitable for use the articulated rail road car of FIG. 2 a;

FIG. 3 a shows a side view of a three unit articulated rail road car,being an alternate embodiment of articulated rail road car to that ofFIG. 2 a;

FIG. 3 b shows a side view of an alternate three unit rail road car toFIG. 3 a;

FIG. 3 c shows a side view of another alternate three unit rail road carto FIG. 3 a;

FIG. 4 a shows a side view of a four unit articulated rail road car,being an alternate embodiment of articulated rail road car to that ofFIG. 2 a;

FIG. 4 b shows a side view of an alternate four unit articulated railroad car to the articulated rail road car of FIG. 4 a;

FIG. 4 c shows a side view of another alternate four unit articulatedrail road car to the articulated rail road car of FIG. 4 a;

FIG. 4 d shows a side view of a further alternate four unit articulatedrail road car to the articulated rail road car of FIG. 4 a;

FIG. 5 a shows a side view of a five unit articulated rail road car,being an alternate embodiment of articulated rail road car to that ofFIG. 2 a;

FIG. 5 b shows a side view of an alternate five unit articulated railroad car to the articulated rail road car of FIG. 5 a;

FIG. 5 c shows a side view of another alternate five unit articulatedrail road car to the articulated rail road car of FIG. 5 a;

FIG. 5 d shows a side view of a further alternate five unit articulatedrail road car to the articulated rail road car of FIG. 5 a;

FIG. 5 e shows a side view of still another alternate five unitarticulated rail road car to the articulated rail road car of FIG. 5 a;

FIG. 6 a shows a side view of a two unit articulated auto-rack rail carhaving the truck layout of the articulated rail road car of FIG. 2 a;

FIG. 6 b shows a side view detail of the auto-rack rail road car of FIG.6 a;

FIG. 6 c shows a top view detail of the auto-rack rail road car of FIG.6 a;

FIG. 6 d shows a cross-section at the main bolster of the auto rack railroad car of FIG. 6 a;

FIG. 6 e shows an alternate cross-sectional view to that of FIG. 6 d;

FIG. 6 f shows an alternate two unit articulated autorack rail road carto that of FIG. 6 a, the rail car units thereof having depressed centerportions;

FIG. 7 a shows a side view of a three unit articulated auto-rack railroad car having the truck layout of the articulated rail road car ofFIG. 3 c;

FIG. 7 b shows a side view of an alternate three unit rail road car toFIG. 7 a;

FIG. 8 a shows a side view of a four unit articulated rail road caranalogous to the two unit articulated rail road car of FIG. 6 a;

FIG. 8 b shows a side view of an alternate four unit articulated railroad car to the articulated rail road car of FIG. 8 a;

FIG. 9 a shows a shortened top view of an articulated well car end unitanalogous to an end unit of the two unit articulated rail road car ofFIG. 2 a;

FIG. 9 b shows a shortened side view of the articulated well car endunit of FIG. 9 a;

FIG. 9 c shows a shortened view of a mating articulated well car endunit to the end unit of FIG. 9 a, and

FIG. 9 d shows a side view of the shortened end unit of FIG. 9 c.

DETAILED DESCRIPTION OF THE INVENTION

The description which follows, and the embodiments described therein,are provided by way of illustration of an example, or examples ofparticular embodiments of the principles of the present invention. Theseexamples are provided for the purposes of explanation, and not oflimitation, of those principles and of the invention. In the descriptionwhich follows, like parts are marked throughout the specification andthe drawings with the same respective reference numerals.

In terms of general orientation and directional nomenclature, for eachof the rail road cars described herein, the longitudinal direction isdefined as being coincident with the rolling direction of the car, orcar unit, when located on tangent (that is, straight) track. In the caseof a car having a center sill, whether a through center sill or stubcenter sill, the longitudinal direction is parallel to the center sill,and parallel to the side sills, if any. Unless otherwise noted,vertical, or upward and downward are terms that use top of rail TOR as adatum. The term lateral, or laterally outboard, refers to a cross-wisedistance or orientation relative to the longitudinal centerline of therail road car, or car unit, indicated as CL-Rail Car. The term“longitudinally inboard”, or “longitudinally outboard” is a lengthwisedistance taken relative to a mid-span lateral section of the car, or carunit.

An articulated rail car is indicated in FIG. 1 c and FIGS. 2 a and 2 bgenerally as 20. Car 20 is preferably an auto-rack rail road car, butcould be another type of rail road freight car, such as a well car, agondola car, a center-beam car, a spine car, a flat car, a box car, orother type of rail road car. It has a first rail car unit 22 and asecond rail car unit 24. They are joined by a connection that may beconceptually idealised as a pin joint capable of transferring alongitudinal axial load and a shear load in any of two axes, but not abending moment, in the nature of an articulation connection 26 locatedbetween units 22 and 24. First rail car unit 22 has a pair of first andsecond ends, 28 and 30, that are, respectively, proximate to and distantfrom articulation connection 26. Second rail car unit 24 has two ends,32 and 34 that are, similarly, proximate and distal ends respectivelyrelative to articulation connection 26. Rail car unit 22 is carriedupon, and supported by, two longitudinally spaced rail car trucks 36 and38 that are located under respective first and second ends 28 and 30.The nominal vertically extending pivot axis of articulation connection26 is indicated as a centerline, ‘CL-Pivot”. The truck centers are eachindicated as ‘CL-Truck’. The mid-span centerline of unit 22 is indicatedas ‘CL-Transverse’.

Second rail car unit 24 is supported at its distal end on a single truck40, located under distal end 34. That is, truck 40 is located closer todistal end 34 of rail car unit 24, than to proximal end 32 of rail carunit 24. Support for proximal end 32 is provided through articulationconnection 26. Notably, articulation connection 26 is not mounteddirectly upon, or above, a truck, but rather is carried at the end of acantilever 41 extending longitudinally from truck 36 toward rail carunit 24. As can be seen, rail road car 20 is free of trucks betweentruck 36 and truck 40, and hence between articulation connection 26 andtruck 40.

Each of trucks 36, 38 and 40 is a double axle truck of customary NorthAmerican construction, having a truck bolster extending perpendicular tothe rail road track, a pair of side frames mounted to the laterallyoutboard ends of the bolster, and two pairs of wheels, each pair ofwheels being mounted on a respective one of a pair of spaced apart axlescarried in the side frames. Each of trucks 36, 38 and 40 is free topivot, or swivel, about the vertical axis of the truck center relativeto the body of its respective rail car unit generally, as may bedetermined by its path along the rails. For example, truck 36 has twoaxles, a first axle 42 and a second axle 44 spaced equally to eitherside of the truck center. Axle 42 lies longitudinally inboard of axle 44relative to the body 46 of first car unit 22. Car body 46 has anoverhanging portion 48 extending outboard of the truck center of truck36, between truck 36 and articulation connection 26. Other types oftruck are known, such as three axle trucks and single axle trucks, andcould be used in place of truck 36. Steerable trucks are a includedamong the other types of trucks.

For the purposes of the present description, unless otherwise stated,distances are measured between the various pivot and truck centers. Thedistance between the truck centers of trucks 36 and 38 is indicated inFIG. 2 a as D₁. The distance from the truck center of truck 36 toarticulation connection 26, namely the cantilever distance, is shown asD₂. The distance from articulation connection 26 to the truck center oftruck 40 is indicated as D₃. The distance between the truck centers oftrucks 36 and 40, when car 20 is sitting on tangent (i.e., straight)track is indicated as D₄. The truck arrangement is asymmetric relativeto articulation connection 26. That is, D₁ is not equal to the distancebetween truck 38 and articulation connection 26, (as it would be, forexample, with a conventional shared truck located beneath thearticulated connector, symmetrically between two rail car bodies). Thedifference in distance is the length of cantilever 41, that is, D₂.Similarly, in the illustrated embodiment of FIG. 2 a, D₃ equals D₁ plusD₂, although in the general case this need not be so.

As noted above, the cantilever distance D₂ is measured from (a) thepivot connection of truck 36 (that is, the truck center of truck 36) to(b) the pivot axis, CL-Pivot, of articulation connection 26. As isevident, the pivot axis is neither longitudinally co-incident with thetruck center of the nearest adjacent truck, namely truck 36, nor is itcarried over the body of truck 36, nor over any other truck. Rather, notonly is the pivot axis, CL-Pivot, longitudinally eccentric relative tothe closest truck center, namely that of truck 36, but moreover, it iscantilevered longitudinally outboard of axle 44, and of truck 36entirely. The structure of car body 46 is such as to permit the verticalshear load passed from second rail car unit 24 through articulationconnection 26 to be carried to truck 38.

In the embodiment illustrated in FIG. 2 a, a rigid center sill 45 ismounted to car body 46, and runs longitudinally inboard above truck 36.Generally, the center sill can be either (a) a through center sillextending fully from articulated connection 26 to coupler 47 at thedistal end of first car unit 22, running above both truck 36 and truck38; or (b) alternatively, it can be a stub center sill, as may beadvantageous to permit a well to be defined between first and secondends 28 and 30, with another stub sill being mounted over truck 38 andextending outwardly thereof to a distal end having releasable coupler 47mounted thereto. Coupler 47, and all other releasable couplers describedherein, are of a type such as to permit, for example, interchangeableservice with rail road freight cars in general service in North America.Similarly, rail car unit 24 has a rigid straight-through center sill 49running inboard of a releasable coupler 47, above truck 40, toarticulation connection 26.

Articulation connection 26 (and the other articulated connections notedherein) is preferably a steel articulated connector, indicated generallyin FIG. 2 c as 50, similar to those commonly available frommanufacturers such as Westinghouse Air Brake (WABCO) of Wilmerding Pa.,or American Steel Foundries (ASF), also known as Amsted Industries Inc.,of Chicago Ill. The general form of one type of articulated connector(with a vertical pin) is shown, for example, in U.S. Pat. No. 4,336,758of Radwill, issued Jun. 29, 1982. In general, this kind of permanent,articulated connection has a female member, in the nature of a femalesocket 52 mounted to a center sill of one articulated rail car unit (inthis instance center sill 45 of unit 22), and a male member 54 mountedto an adjacent rail car unit, (in this instance center sill 49 of unit24), as shown in FIG. 2 c. FIG. 2 c is not necessarily to scale, and maynot show all detail features of an articulated connector. It is providedfor the purposes of conceptual illustration.

Male member 54 has an extension, or nose, 56 that seats in female socket52. A main pivot pin 58 extends through a bore defined in top plate 6Gof socket 52, through a bore, or passage 62 in male member 54, andthrough the base plate 64 of female socket 52. Pivot pin 58 is nominallyvertical. That is, on straight, level track pin 58 is vertical. In aconventional arrangement in which the articulated connection is mountedover a truck, another pin may extend from blind bore 65 of pin 58 toseat in the central bore in the truck center plate. Notably, in theembodiment illustrated in FIG. 2 b, pin 58 is not supported over atruck.

Male member 54 has three rotational degrees of freedom relative tofemale socket 52. First, it can yaw about the main pivot axis, as whenthe car units negotiate a bend or switch. Second, it can pitch about atransverse horizontal axis, as when the car units change slope at thetrough of a valley or the crest of a grade. Third, the car units canroll relative to each other, as when entering or leaving super-elevatedcross-level track, (that is, banked track). It is not intended that malemember 54 have any translational degrees of freedom relative to femalesocket 52, such that a vertically downward shear load V can betransferred from male member 54 into female socket 52, with little or nolongitudinal or lateral play. To permit these motions, female socket 52has spherical seat 66 having an upwardly facing bearing surfacedescribing a portion of a spherical surface. Another mating sphericalannular member 68 sits atop seat 66, and has a mating, downwardlyfacing, bearing surface describing a portion of a sphere such that aspherical bearing surface interface is created. Member 68 also has anupwardly facing surface upon which male member 54 sits. An insert 70 hasa cylindrical interface lying against pin 58, and a spherical surfacethat engages a mating spherical surface of passage 62 lying on theinside face of nose 56. A wedge 72 and wear plate 74 are located betweennose 56 and the inner wall, or groin, 76, of female socket 52. Wearplate 74 has a vertical face bearing against wedge 72, and a sphericalface bearing against a mating external spherical face of nose 56. Wedge72 bears against wear plate 74, as noted, and also has a tapered facebearing against a corresponding tapered face of groin 76. The tapers areformed such that as wear occurs, gravity will tend to urge wedge 72downwardly, tending to cause articulated connector 50 to belongitudinally slackless.

In the example of FIGS. 2 a and 2 b, it is preferred that male member 54be mounted to the end of the center sill (e.g., 49) of the car unit endthat does not have a truck, such as end 32 of car unit 24, and thatfemale socket 52 be mounted to center sill 45 of the two-truck car unit22. In this way the vertical shear from car unit 24 is transferred intothe cantilevered overhang of car unit 22 through the sphericalinterface. By way of an alternative, it appears that in principle, malemember 54 could be mounted inversely on car unit 22, and female socket54 could be mounted inversely on car unit 24, with appropriate changesin the location and orientation of the annular members and sphericalinterfaces, and in the operation of the wedge and wear plate. However,for simplicity, it is advantageous to use existing articulatedconnectors, installed in the upright orientation addressed above.

The scope of the allowable roll of one car unit relative to the nextadjacent car unit is limited by a pair of side-bearing arms 61, 63mounted to rail car unit 22, and mating side-bearing arms 65, 67 mountedto rail car unit 24. In FIGS. 2 a and 2 b, side bearing arms 61, 63 and65, 67 are shown at a higher elevation than articulation connection 26.This is done for the purposes of conceptual illustration only. Ingeneral, side bearing arms tend to be mounted at a height at which theirbearing interfaces lie in, or are roughly level with, the horizontalplane (when the cars units are sitting on straight, level track) passingthrough the center of curvature of the spherical surfaces of thearticulated connector. All of the rail road car embodiments describedherein employ side-bearing arms, the side bearing arms of the adjacentfirst and second rail car units being mutually engaging. The sidebearing arms have been omitted, for clarity, from FIGS. 3 a to 5 e, 6 a,6 f, and 7 a to 8 b.

In the embodiment of FIG. 3 a, an articulated rail road car 80 hasfirst, second, and third rail car units 82, 84, and 86. Rail car units82 and 84 are joined together by an articulation connection 88, thefemale portion, or socket being mounted to unit 82, and the male portionbeing mounted to unit 84. Rail car units 84 and 86 are also joinedtogether by an articulation connection 90, the female portion ofconnector 90 being mounted to unit 84, and the male portion beingmounted to unit 86. Rail car unit 82 is substantially the same as railcar unit 22 described above. Rail car unit 84 is substantially the sameas rail car unit 24 described above, but has articulation connectionsmounted at both ends, namely 88 and 90. Rail car unit 86 issubstantially the same as rail car unit 24.

It will be understood that additional rail car units having articulationconnections at both ends, such as rail car unit 84, can be addedintermediate rail car end units having one releasable coupler end, suchas rail car units 82 and 86, to yield a longer string of rail car units.A four-unit rail road car having a further intermediate unit 84, exampleis shown in FIG. 4 a as 92. A 5-unit rail road car having threeintermediate units 84 is shown in FIG. 5 a as 94.

In the embodiment of FIG. 3 b, an articulated three-pack rail road caris indicated generally as 100. It has a middle unit 102 and a pair offirst and second end units 104 and 106. Middle unit 102 is substantiallysimilar to unit 22 described above. However, it differs in havingcantilevered articulation connections 26 mounted at both ends of athrough center sill 108. Each of end units 104 and 106 is a single truckunit substantially the same as unit 24 described above. Middle unit 102is a two truck unit, and can be thought of conceptually as a car unitmade up of two articulation connection ends joined together. Each of theends of unit 102 has a female portion of respective articulationsconnection 26, the corresponding male portions being mounted on units104 and 106. Articulation connections 26 are mounted longitudinallyoutboard of respective first and second two-axle, four wheel swivelmounted (i.e., pivoting) trucks 112 and 114. As above, the pivot axis ofthe articulation connections is thus eccentric relative to the closestrespective truck center.

In the embodiment of FIG. 3 c, an alternative articulated three-packrail road car is indicated generally as 120. It has a middle unit 122and a pair of end units 124 and 126. Each of end units 124 and 126 isthe same as unit 22 described above. Middle unit 122 is a trucklessunit, being supported at the articulation connection 26 at either end.That is, rail road car 120 is free of trucks between the longitudinallyinboard trucks 128 and 129 of units 124 and 126 respectively. As above,each articulation connection 26 includes a male portion mounted to carunit 122 and mating with female portions mounted to end units 124 and126.

In the embodiments of cantilevered articulation connection shown anddescribed above, in contrast to the shared-truck articulation connectionB30 of rail road car B20, and the shared truck articulation connectionsof rail car C20, the articulation points of the articulated connectorsof rail road cars 20, 80, 100, and 120 lie to the outside of the trackcenterline as the rail road car moves along a curve. This is shown, forexample, by articulation connection 26 in FIG. 1 c, and by articulatedconnections 26 of rail road car 100 in FIG. 1 e. This outward positionrelative to the track centerline locates the outer corners 29 and 31rail car units 22 and 24 adjacent to articulated connection 26 outboard,closer to R₃. The offset distance, 63, of rail road car units 22 and 24is the same as δ₁ shown for rail car units B22 and B24. The length ofcar unit 22 exceeds the length of car unit B22 by the length of theoverhang, while tending not to require a reduction in car body widthrelative to car unit B22. Similarly, rail car unit 24 also exceeds thecorresponding length of rail car unit B24 by the same, or roughly thesame, overhang distance since the point at which the rail car bodycenterline of rail car unit 24 crosses over the track centerlinelongitudinally inboard of articulation connection 26, indicated roughlyas 33 in FIG. 1 c, is roughly equivalent to the point at which rail carunit B24 has articulation connection B30. Thus rail car unit 24 islonger than rail car unit B24, and yet may tend not to require areduction in width relative to car unit B24.

The comparisons of FIGS. 1 d, 1 e and 1 f, show a first differencebetween rail road car C20 and rail road car 100. Although the width ‘W’of car unit 102 is the same as car unit C22, and the truck centerdistance, L₁, is also the same, the length of car unit 102 between thepoints of articulation is greater, being equal to L₁ plus twice thelength of the cantilever distance L₂ to the articulation connections 26at each end of car unit 102. Whereas the car body length L₃ of rail carunit C22 is shorter than the truck center distance, L₁, by contrast, thecar body length L₄ of rail car unit 102 exceeds the truck centerdistance L₁ by twice the body overhang dimension, L₅. Notably, while theexternal corners of car unit C22 lie well clear on the inside of R₃, theexternal corners 103 and 105, and adjacent corners 107 and 109 of carunits 104 and 106 respectively, are shown running along R₃. The car bodylength, (L₃ for car unit C20, L₄ for car unit 102) is a measure of theuseful loading length, and is taken in each case as the overall decklength dimension over the endmost lateral cross members, whether endsills or end bolsters, as the case may be, of the rail car unit. In eachcase, (a) the point of articulation (i.e., the pivot centerline) lieslongitudinally outboard of the end sill, or end bolster; and, (b) theend sill or end bolster lies longitudinally outboard of the of thenearest truck center pivot axis.

The comparison illustrations of FIGS. 1 g and 1 h show a second effect.End car unit 104 is longer than end car unit C24, again by the overhangdistance, indicated as L₂. For the purposes of simplicity of explanationand illustration, the car bodies in all of FIGS. 1 a to 1 h have beenshown as being rectangular, with no tapering of their ends. Similarly,as illustrated in FIG. 1 e, the length of car unit 104 has been chosensuch that the distance from the truck center of its single truck toarticulation connection 26 between rail car units 102 and 104 is equalto L₁ plus L₂. It is then a matter of geometry that the longitudinalcenterline of car unit 104 will fall over the centerline of the track ata “phantom truck center” location, indicated as 117, located L₁ awayfrom the truck center of truck 115. In a conventional articulated carunit, such as car unit C24, this would be the location of the point ofarticulation, and hence of a shared truck of a shorter car unit.However, as noted, car unit 104 extends beyond this point ofintersection, and the rail car unit centerline diverges from the trackcenterline. This divergence is called swing-out.

The swing-out of the point of articulation is defined as the distance,measured perpendicular to the track centerline, from the trackcenterline to the pivot axis of the point of articulation. It is shownin FIG. 1 g as ε. In a conventional articulated rail road freight car εis nil, since the point of articulation is coincident with the pivotaxis of the shared truck, and rides over the track centerline as shownin FIG. 1 h.

The outline of the body of rail car unit 104 is shown in FIG. 1 h inintermittent dashes and dots, and indicated as 104 a. It has width ‘W’,the same as unit 102. The outline of the body of rail car unit 104, asif it had no swing-out (i.e., ε=zero) is shown in solid line as 104 b,also being of width ‘W’. As can be seen, the inside edge of 104 bcrosses into the impermissible zone lying to the inside of R₂. Thenarrower outline of the body of rail car 104, having an ε of zero, like104 b, and having the same length as 104 a, yet remaining outside the R₂boundary, is shown in dashed lines as 104 c. As can be seen, 104 c isnarrower than 104 a. That being the case, and ε being very smallrelative to (L₁+L₂), taking truck center 115 as a point of rotation, bysimilar triangles the swing out at articulation connection 26 betweenrail car units 102 and 104 moves the inside edge of the car at mid spanbetween 115 and 117 radially outward relative to R₁, R₂ and R₃ adistance smaller than, but proportionate to, ε. The net effect is thatswing-out tends to permit a wider car than otherwise, or to permit agreater car length for the same width as previously used.

In summary, conceptually, placement of the articulation connectionlongitudinally outboard of the truck centers can be thought of in termsof the additional car length that can be obtained by having an overhang,without changing the width of the car. It can also be thought of interms of the cantilever arm forcing the centerline of the adjacent carunit outward relative to the radius of curvature of the centerline ofthe track, such that the adjacent rail car body can be wider than itcould be if the articulation were not cantilevered.

Further, although the various embodiments illustrated herein showarticulated connectors mounted to overhang beyond the closest adjacenttruck to obtain the full benefit of car length possible within a givencar plate envelope, some of this benefit can be obtained from lesserlongitudinal eccentricity between the truck center and the pivot center,since even a partial eccentricity will cause the inboard deck edge ofthe car having the male articulated connection portion to ride furthertoward the outside of the track than otherwise.

The remaining multi-car embodiments shown in FIGS. 4 b to 4 d and 5 b to5 e can be assembled from rail car units of the types described above.For example, the embodiment of FIG. 4 b shows an articulated rail roadcar 130 that has a single-truck first end unit 132 that is the same asend unit 24; a two-truck intermediate rail car unit 134 that is the sameas rail car unit 102; an intermediate single-truck unit 136 that is thesame as unit 84, and a second single-truck end unit 138 that is the sameas unit 24. FIG. 4 c shows an articulated rail road car 140 that has afirst two-truck end unit 142 that is the same as unit 82; a trucklessintermediate unit 144 that is the same as truckless unit 122; a twotruck intermediate unit 146 that is the same as unit 84; and a singletruck end unit 148 that is the same as unit 24.

It is also possible to join adjacent rail car units with a combinationof slackless draw bar connections and articulation connections. Forexample, in the embodiment of FIG. 4 d, a partially articulated,partially draw-bar connected rail road car assembly 150 has a pair oftwo truck intermediate units 152 and 153 that are similar to unit 102,and a pair of single truck end units 154 and 155 that are similar tounit 24, but rather than having an articulated connection, units 152 and153 are joined at their adjacent ends by a draw bar connection,indicated schematically as 156. Where a draw bar is used, there is 25 anadjacent rail car truck 157, 158 supporting the near end of each or theadjacent rail car units 152, 153 lying to either side of the draw bar.It would be possible, alternatively, to make a four-unit articulatedrail road car by joining two pairs of rail road car units, such as 22and 24, at the truck ends of their single truck rail car units, (i.e.,24) with a draw-bar in place of releasable coupler 47.

In FIG. 5 b, an articulated rail road car 160 has an interior two-truckrail car unit 162 that is the same as unit 102, one single-truck endunit 164 connected to one end of unit 162, unit 164 being the same asunit 24; two intermediate units 166, 167 that are the same as unit 84,and a further single-truck end unit 168 that is the same as unit 24.

In the embodiment of FIG. 5 c, an articulated rail road car 170 has aninterior, middle two-truck unit 172 that is the same as unit 102, a pairof first and second oppositely oriented intermediate single-truck units174, that are each the same as unit 84, and a pair of first and secondsingle-truck end units 176 that are the same as unit 24. In theembodiment of FIG. 5 d, an articulated rail road car 180 has an internaltwo-truck middle unit 182 that is the same as unit 102, a pair oftwo-truck end units 184 that are the same as unit 22, and a pair ofintermediate truckless units 186 that are the same as unit 122. In theembodiment of FIG. 5 e, an articulated rail road car 190 has a pair offirst and second oppositely oriented single-truck end units 192 that arethe same as unit 24, a pair of intermediate two-truck units 194 that arethe same as unit 102, and a middle, truckless unit 196 that is the sameas unit 122. Other combinations and permutations of these rail car unitsare possible.

Other multi-unit articulated rail road cars, or partially articulatedrail road cars, having a larger number of rail car units can beassembled from the various types of rail car units noted above, whetherone truck, two-truck, or truckless, and whether they are end units orintermediate units. In general, in each example there is an articulatedrail road car having a plurality of rail car units, supported on asuitable number of rail car trucks to permit the articulated rail roadcar to roll in a longitudinal direction on rail road tracks. In eachcase there is at least one articulation connection lying between a pairof adjacent, first and second rail car units, the articulationconnection being longitudinally cantilevered relative to the nearest ofthe rail car trucks. That is, none of the rail car trucks is mountedcentrally under the cantilevered articulation connection.

FIG. 6 a shows a two-unit articulated auto rack rail road car 200 thatis similar to articulated rail road car 20 in layout. It has a two-truckfirst unit 202 and a single truck second rail car unit 204, joined at anarticulation connection 206. Unit 202 has first and second end portions208 and 210, each of which is mounted over a freely pivoting fourwheeled truck 212, 214 respectively. First end portion 208 is proximateto connection 206, and second end portion 210 is distant from connection206. Second end portion 210 has a conventional releasable coupler 215mounted thereto for connection to other cars in interchangeable service.

Unit 204 has first and second end portions 216 and 218, end portion 216being proximate to connection 206 and end portion 218 being distanttherefrom. Unit 204 has a single freely pivoting four-wheeled truck 220located under end portion 218. Second end portion 218 is substantiallythe same as second end portion 210, and, similarly, has a conventionalreleasable coupling 215 for interchangeable service. In this way,two-truck rail car unit 202 is a two-truck end unit, and rail car 204 isa single truck end unit.

Each of units 202 and 204 has a body 222, 223 having an upwardlyextending enclosure structure for housing vehicles to be carried, suchas automobiles, indicated generically as 224, 225. A decking structure226, 227 is mounted within body 222, 223. In the embodiment illustratedin FIG. 6 a, decking structure 226, 227 is a triple deck structure thatincludes a flat main deck 228, 229, an upwardly spaced middle deck, 230,231 and a further upwardly spaced upper, or top deck 232, 233. Aspanning assembly in the nature of main, middle and top pairs of bridgeplates 234, 235, 236 extend between decking structures 226 and 227 topermit longitudinal loading of vehicles from one car unit to the next inthe manner known as circus loading. The gap between enclosure structures224 and 225 is enclosed by a flexible structure in the nature of abellows 238. The open ends of enclosure structures 224 and 225 andenclosed by moveable closure members in the nature of doors 240, 241,typically of the type often referred to as a “radial arm door” employinga monolithic door panel having a curved portion and a tangent portionand a radial arm extending from a point of rotation to the door panel.The doors are moveable between open positions for loading anddischarging vehicles, to a closed position tending to keep out rain,snow, stones, vandals and thieves.

Details of autorack rail car 200 of FIG. 6 a are illustrated generallyin FIGS. 6 b, and 6 c, with the upper and middle decks, bridge plates,bellows and side panels removed. Each of car units 202 and 204 has amain center sill 242, 243; a pair of left and right hand side sills 250,252 and 251, 253; and an array of cross-bearers 254, 255 extendinglaterally between center sill 242, 243 and side sills 250, 252, 251, 253at the longitudinal stations of an array 256, 257 of upright posts 258,259.

Posts 258, 259 are, typically, on roughly 4 ft centers. Posts 258, 259extend upwardly to a top chord member 260, 261, to which a roof canopyof transversely corrugated steel sheet 262 is mounted. Each of posts258, 259 is provided with a gusset plate 264 to improve the momentconnection to side sill 250, 252 or 251, 253, respectively. The last, ormost longitudinally outboard of posts 258 or 259 is sometimes referredto as the “number 1” post indicated as 263, and the penultimate (i.e.,second to last) post, namely the next longitudinally adjacent inboardpost is referred to as the “number 2” post, indicated as 265. A diagonalbrace 266 extends upwardly from the base of the “number 1” post 263toward the juncture of the “number 2” post 265 with each respect “number1” post 263.

Car unit 202 has a laterally extending main bolster 270 mounted at thelongitudinal location of the truck center of truck 212, such that thelaterally outboard distal extremities of main bolster 270 meet sidesills 250, 252 at the longitudinal station of the root of the “number 2”post, 265. An endmost lateral structural member in the nature of an endbolster 272 extends laterally outboard from main center sill 242 to meetthe ends of side sills 250 and 252. (In this, or other, examples, theendmost lateral structural member can be either an end bolster or an endsill, or other suitable cross-member). A main deck shear plate 274 ismounted upon the upper flanges of main center sill 250, main bolster270, end bolster 276 and cross-bearers 254 and extends laterally betweenside sills 250, 252. At the longitudinally outboard end portion 210 ofcar unit 202, that is, the end furthest from articulated connection 206,rail road car 200 has a similar underframe construction of main bolster,end bolster and cross-bearers and shear plate. It differs in having aconventional draft sill and releasable coupler 215 for interchangeableservice connection with other rail road cars. The upper portion of FIG.6 b is shown with the respective shear plates removed to reveal theunderlying bolster structure.

Rail car unit 204 has a conventional underframe structure at itslongitudinally outboard end portion, 218, with main bolster, endbolster, cross bearers, shear plate, draft sill and interchangeablecoupler in the same manner as end 210 of unit 202. At the inboard endportion 208 of car unit 204, the underframe structure differs in havingmerely an end bolster 278, and cross-bearers 280, but no main bolster,and a straight through main sill end of constant section to the endbolster, there being no truck to be accommodated.

A female articulated connector portion 282 is mounted to the end ofcenter sill 242 of car unit 202. A male articulated connector portion284 is mounted to the inboard end of main center sill 243 of rail carunit 204, portions 282 and 284 being designed to mate and to be heldtogether with appropriate bearing surfaces and a pin, such as describedabove. Female articulated connector portion, 282, is bracketed by a pairof left and right hand female side-bearing arms 286, 288. Arms 286 and288 are splayed outwardly. Longitudinal structural reinforcementmembers, in the nature of a pair of first and second left and right handbeams 290, 292 are carried longitudinally inboard from the root of arms286 and 288, to terminate at main bolster 270.

Male articulated connector portion 284 is bracketed by a pair of leftand right hand male side bearing arms 287 and 289. Arms 287 and 289 aresplayed outwardly. Longitudinal structural reinforcement members, in thenature of a pair of first and second, left and right hand beams 291, 293are carried longitudinally inboard from the root of arms 287 and 289, toterminate at the second inboard cross-bearer located at the longitudinalstation of the “number 2” post 265, indicated as 290.

Side bearing arms 286, 288, and 287, 289 engage in the manner of sidebearing arms generally, with female arms 286 and 288 having upwardlyfacing bearing surfaces 292, 294, and male side bearing arms 287, 289having downwardly facing bearing surfaces 293, 295. The arrangement ofthe male and female bearing surfaces could be reversed. However, inoperation this reversal could tend to increase the vertical reactioncarried in the female portion 282 of articulated connector 286, whereasthe arrangement shown would tend not to.

FIG. 6 d shows a cross-section of car unit 202 at the truck center oftruck 212, and shows a tri-level configuration of main, middle and upperdecks 228, 230 and 232 for carrying automotive vehicles. Each of themiddle and upper decks has a slight crown, and has knee braces 296mounted to posts 258. FIG. 6 e shows a similar cross section of analternative car unit in a bi-level configuration, with a main deck 228and an upper deck 298. A thin-shelled corrugated steel roof structure299 is shown mounted to span the width of car unit 202 above the decksbetween the top chords.

In the alternative embodiment of FIG. 6 f, another two unit, articulatedauto-rack rail road car is indicated as 300. It has first and secondunits 302 and 304 that are broadly similar to units 202 and 204, butdiffers from them in having wells 305, 307 located inboard of trucks306, 308 and 310 between respective pairs of side sills 312, 314, ratherthan a flat main deck. The body of each of units 302 and 304 employs atruss structure 316, 318 having a substructure that includes side sills312, 314, a superstructure that includes an overhead framework 320, 321having transverse frames and longitudinal stringers, and an intermediateshear force transfer assembly in the nature of pairs of laterally spacedside webworks 322, 323. Each of side webworks 322, 323 includes an arrayof posts 324, 325 and diagonal bracing 326, 327. Side web works 322, 323extend vertically between side between the substructure and a pair oftop chord members 328, 329. The transverse frames of overhead framework320, 321 are mounted on top chord members 326 at the longitudinalstations of posts 324. In this way the superstructure, substructure, andintermediate shear force transfer assemblies co-operate, and tend tofunction in the manner of a box truss.

In further alternative embodiments, units 202 and 204 could be madeusing a similar truss construction to units 302 and 304, or, conversely,units 302 and 304 could be fabricated with a thin-shelled roof structureas shown in FIGS. 6 b, 6 d and 6 e.

Inasmuch as the cross-section of autorack rail car units 202 and 204 isthe same at mid span, a car unit having two trucks, and articulationconnections at each end can be manufactured by using two end portions208, as shown in FIG. 6 b, 6 c mounted to form a single body.Alternatively, a truckless car unit can be manufactured using twotruckless end portions, such as end portion 216, in a single body, andan internal single truck car unit can be manufactured using an endportion such as end portion 208 of unit 202 and an end portion such asend portion 216 of unit 204, mounted together to form a single body. Inthis way, a variety of types of car can be produced to yield the variousstrings of cars units described below.

FIG. 7 a shows a three-pack articulated auto rack rail road car 330having the same general layout as articulated rail road car 80 of FIG. 3b. Rail road car 330 has a truckless middle unit 332 and a pair oftwo-truck end units 334 and 336. Each of end units 334 and 336 has thesame construction as unit 202 of articulated rail road car 200 describedabove. Unit 332 however, is truckless. That is, unit 332 is supported ateither end at articulation connections 338 and 340, but is not otherwisesupported by any truck between trucks 342 and 344 of units 334 and 336.Conceptually, unit 332 can be thought of as having two end portions 346and 348, each of which is like end portion 216 of car unit 204, joinedtogether.

FIG. 7 b shows a three-pack articulated auto-rack rail road car 350 thathas the same general layout as articulated rail road car 100 of FIG. 3a. That is, it has a two-truck middle unit 352, and a pair of singletruck end units 354 and 356. Each of units 354 and 356 has the sameconstruction as auto-rack rail car unit 204. Rail car unit 352 has apair of freely pivoting trucks 358 and 360 and articulated connectors atboth ends. The general construction of car units 352,354 and 356 is asdescribed above for car units 202 and 204.

Rail road car 350 shows the preferred truck layout of the presentinvention-that is, an articulated three pack auto rack rail road carwith a two truck middle unit, with single truck end units to eitherside, and cantilevered articulated connectors lying outboard of therespective trucks of the middle car unit. Although the rail road cars ofFIGS. 7 a, 7 b, 8 a and 8 b are shown in tri-level configuration, itwill be understood that they can be made in either bi-levelconfiguration, or tri-level configuration, or with movable decksconvertible between bi-level and tri-level configurations. In thepreferred embodiment, the decks are fixed, and in bi-level configurationas shown in FIG. 6 e. In the preferred embodiment, in bi-levelconfiguration, the spacing between the truck centers of the two-truckmiddle car unit is 57 ft. 9 in., that is, a distance greater than thebase car truck center distance of 46 ft. 3 in. The distance from thenearest truck center to the articulated connector is 12 ft. 1 in. Thedistance between the articulated connectors is then 81 ft. 11 in. Thedistance from the articulated connection to the adjacent single end unittruck at either end is 69 ft. 10 in. with a 14 ft. 1 in. overhang to thestriker face. The overall length of the three pack is 249 ft 9 in., suchthat a pair of three pack cars coupled together yields a nominal designlength of 499 ft 6 in. An example of dimensions for a correspondingtri-level three-pack auto rack rail car are 55′-0″ truck centers for thetwo truck middle car unit; truck to articulation, 8 ft, 3.5 in.; betweenarticulations 71 ft. 7 in.; from the articulations to the single endunit trucks is 58 ft. 6 in.; the end unit overhang is 13 ft. 7-[¾] in.;and the overall tri-level three pack length is approximately 218 ft.

FIG. 8 a shows a four unit articulated auto-rack car 370. It hasindividual single truck rail car end units 372, 373, and internal doubletruck rail car units 374, 375. End car units 372 and 373 have the samelayout and construction as car unit 204 of FIG. 6 a. Internal car units374 and 375 have the same general construction as car unit 202 of FIG. 6a, but rather than having a releasable coupler at the end remote fromtheir respective single truck adjacent units, car units 374 and 375 areconnected at their common end by a slackless draw bar 378.

FIG. 8 b shows another four unit articulated auto-rack rail road car,380. It has a two truck end rail car unit 382 of the same constructionas two truck end unit 202 of FIG. 6 a; a single truck end unit 384 thathas the same construction as single truck end unit 204, a two truckintermediate unit 386 that has the same construction as middle unit 352,and a truckless intermediate unit 388 that has the same construction asmiddle unit 302, described above.

The end portions of the car units shown in FIGS. 6 a to 6 f, 7 a and 7 band described herein can be assembled to produce single truck rail carend units, single truck intermediate rail car units, trucklessintermediate units, two truck intermediate units, and two truck endunits. In that light, the car units described can be assembled andarranged to produce many other combinations of rail road cars havingcantilevered articulations, whether 2, 3, 4, 5, 6, 7 or more units in anarticulated rail road car, including auto rack rail road carscorresponding to each of the examples of FIGS. 2 a to 5 e. Further, thegeneral construction of either the units of rail road car 200 or of railroad car 300 can be employed. In addition, although the abovedescription applies to multi-level auto-rack cars, it can also beapplied to single deck articulated rail road cars for carrying vehicles.A single deck articulated rail road car, without side wall structures,and without an overhead roof structure can also be constructed, such asfor carrying larger vehicles, highway trailers or other intermodalcargo.

FIGS. 9 a, 9 b, 9 c and 9 d show abridged top and side views of twounits of an articulated well car 400 such as may be employed fortransporting intermodal containers or highway trailers, or a combinationof containers and highway trailers. FIGS. 9 a, 9 b, 9 c and 9 d havebeen abridged to omit the central portions of the units of car 400, sothat the end portions may be shown in a larger proportion. The views aretruncated longitudinally inboard of the first container supportcross-member, the cross-section of the car between those cross-membersbeing constant, with transverse cross-members spaced longitudinally toprovide support for the various containers support pedestals or cones,or highway trailer rear wheel sets as required conventionally.

Rail road car 400 has a first end unit 402, and a second end unit 404,joined at an articulated connection 406 that has a first, or femaleportion 408 mounted to first end unit 402, and a second, or male portion410 mounted to second end unit 404. Portions 408 and 410 engage, andwhen mated, are held together by a nominally vertical pin, as notedabove.

First end unit 402 is a two-truck end unit, having a first end portion412 proximate to articulation connection 406, and a second end portion414 distant from connection 406. A first, freely pivoting two axle railcar truck 416 is mounted under second end portion 414. Another freelypivoting two axle rail car truck and 418 is mounted under first endportion 412 Inboard truck 418 has larger wheels, and a larger carryingcapacity, than outboard truck 416. That is, outboard truck 416 has 33inch diameter wheels. Inboard truck 418 has 38 inch wheels.

The distal end, that is, the longitudinally outboard end of portion 414carries a standard releasable coupling (not shown) for connection withthe couplers of other rail cars in interchange service.

Rail car unit 402 has structural longitudinal central beam members inthe nature of a first, outboard stub center sill 420, and a second,inboard stub sill 422. It also has transverse structural members in thenature of a first, outboard main bolster 424 (shown in hidden lines)extending perpendicularly laterally from outboard stub sill 420 at thelongitudinal location of the truck center of outboard truck 416; aninboard main bolster 426 extending laterally perpendicular to inboardstub sill 422 at the location of the truck center of inboard truck 418;a first end bolster 428 located parallel to, and longitudinally outboardof, first main bolster 424; a second end bolster 430 located parallelto, and longitudinally outboard of second main bolster 426 (that is,toward articulation connection 406). A pair of laterally spaced, deepside sills 432 and 434 extend the length of rail car unit 402 betweenend bolsters 428 and 430, and mate also with the outboard ends of thewings of main bolsters 424 and 426. Outboard stub center sill 420 has aninboard termination at a transverse bulkhead 436 that extends betweenside sills 432 and 434. Similarly inboard stub center sill 422 has aninboard termination at a transverse bulkhead 438, also extending betweenside sills 432 and 434.

It can thus be seen that a well 440 is defined between side sills 432and 434, and longitudinally between bulkheads 436 and 438. Well 440 isprovided with cross members 442 extending between side sills 432 and440, the cross members having container supports members or pedestals444. Floor pans 446 are also provided for supporting the wheel sets ofhighway trailers, as may be required.

A pair of pin-jointed diagonal load spreading beams 448 and 450 extendbetween a footing 452 whence loads are passed to and from stub centersill 420, to inboard terminations mounted to first cross beam 454. Ashear plate 456 overlies the cruciate form of stub center sill 420 andmain bolster 424 and extends to side sills 432 and 434. A hitchmounting, to which a highway trailer hitch plate can be pivotallyaffixed is shown as 456. Hitch mounting 456 is located over thelongitudinal centerline of unit 402, at the longitudinal station of mainbolster 420.

Similarly, at the far end of well 440, a pair of pin-jointed diagonalload spreading beams 449 and 451 extend between a footing 453 whenceloads are passed to and from inboard stub center sill 422, to inboardterminations mounted to first cross beam 455. A shear plate 457 overliesthe cruciate form of stub center sill 422 and main bolster 426 andextends to side sills 432 and 434. A hitch mounting, to which a highwaytrailer hitch plate can be pivotally affixed is shown as 459. Hitchmounting 459 is located over the longitudinal centerline of unit 402,over main bolster 422.

Each of side sills 432 and 434 has a middle portion 431 of constantdepth, and end portions 433 and 435 of reduced depth to clear therespective trucks. The top chord member 437 of each of side sills 432,434 is carried through the full length of the car. The bottom chordmember 439, and the web member 441 connecting top chord member 437 andbottom chord member 439, are both cut short to accommodate the trucks,416 and 418. The wheel rebate 443 so formed is bordered by an upsweptflange, or fender 445 that sweeps upwardly on a curve from bottom chord439 at the end of middle portion 431. A tapered hollow longitudinalreinforcement beam 447 is mounted above, and runs along, each of topchord members 437 between the respective end bolster and well 440,giving a greater depth of section to end portions 433 and 435.

The end portion 414 of rail car unit 402 is constructed in the manner ofa rail car termination end for interchangeable connection with otherrailroad cars generally. By contrast, end portion 412 of rail car unit402 is an internal end to which an articulated connector portion, namelyfemale articulated connector portion 470 is mounted. Female articulatedconnector portion 470 is mounted in a pocket formed between theupstanding side webs, and the bottom flanges of the longitudinallyoutboard extending end of stub center sill 420, and a false flange, orweb, welded inside center sill 420 below the level of shear plate 457.

As shown in the side view of FIG. 9 b, center sill 420, side sills 432and 434, and shear plate 457 all extend longitudinally outboard of thelongitudinal station of the truck center CL-Truck of truck 418, suchthat there is a cantilevered overhang, indicated generally as 464, towhich the connection means, namely female connection portion 460 iswelded. Truck 418 has an inboard axle 466, an outboard axle 468, sideframes 470, and a truck bolster 472 that lies under main bolster 426. Ascan be seen in FIG. 9 b, the center pin axis CL-Pivot, defining thelocation from which articulation connection 406 is measured, is locatedoutboard of the distal extremity of overhang 464. The longitudinaloffset is the distance between CL-Pivot and CL-Truck. Not only is thepivot centerline, and hence connection 406 longitudinally eccentricrelative to the truck center, but it is cantilevered outboard a distancelying beyond the axis of outboard axle 468, lies fully outboard of truck416 generally, and lies outboard of the endmost lateral structuralmember, namely end bolster 430, as well.

A pair of inverted side bearing arms 480 and 482 are mounted to, andextend longitudinally outboard from, end bolster 430 to bracket femalearticulated connection portion 406. Reinforcements, that is, a pair oflongitudinally extending stiffening members in the nature of steel beams484 and 486, are mounted intermediate stub center sill 426 and sidesills 432 and 434, respectively, such that they mate with end bolster430 at the lateral station corresponding to the root of each of sidebearing arms 480, 482. Beams 484, 486 run inwardly to terminate at mainbolster 426. Gussets are located opposite the webs of beams 484, 486 toprovide web continuity at the junctions with main bolster 424 and endbolster 428. It will be noted that side bearing arms 480, 482 havebearing surfaces 490, 492 that face upwardly. A brake valve mountingbracket 494 extends from side bearing arm 492.

Car unit 404 is shown in FIGS. 9 c and 9 d in abridged top and sideviews. Car unit 404 has a distal end portion 500 located away fromarticulated connection 406, and a proximal end portion 502 to which malearticulated connector portion 410 is mounted. Distal end portion 500 issubstantially identical to distal end portion 420 of first rail car unit402, described above, the same item numbers being used to identify thevarious components.

Proximate end portion 502 is significantly different in construction toend portion 412 of unit portion 402. End portion 502 has a mainstructural longitudinal central beam member in the nature of a first,inboard stub center sill 503. End portion 502 has transverse structuralmembers in the nature of an end bolster 506 located at the end of stubsill 503 immediately adjacent male articulated connector portion 410 andrunning laterally outboard to side sills 508 and 510; and a secondinboard end bolster cross-member, or bolster 512 located parallel to,and longitudinally inboard of, end bolster 506 (that is, in alongitudinal direction away from articulation connection 406). Inasmuchas unit 404 does not have a truck at proximal end portion 502, it doesnot have a main bolster with a fitting to mate with a truck. It alsodoes not have a wheel well, or side sill rebate. Rather, side sills 508and 510 continue at full depth to a vertical corner post 516. Stubcenter sill 503 has an inboard termination at a transverse bulkhead 515that extends between side sills 508 and 510.

It can thus be seen that a well 520 is defined between side sills 508and 510, and longitudinally between bulkheads 516 and 515. Well 520 isprovided with cross members 522 extending between side sills 508 and510, the cross members having container supports members 424. Floor pans426 are also provided for supporting the wheel sets of highway trailers,as may be required.

As described above in the context of rail car unit 402, a pair ofpin-jointed diagonal load spreading beams 528 and 530 extend between afooting 532 whence loads are passed to and from stub center sill 503, toinboard terminations mounted to first cross beam 534. A shear plate 536overlies the H-shaped form of stub center sill 503, end bolster 506 andinboard bolster 512, and extends to side sills 508 and 510. A hitchmounting, to which a highway trailer hitch plate can be pivotallyaffixed is shown as 538. Hitch mounting 538 is located over thelongitudinal centerline of unit 404, between bolsters 506 and 512.

In summary, the end portion 500 of rail car unit 404 is constructed inthe manner of an external rail car termination end for interchangeableconnection with other railroad cars generally. By contrast, end portion502 of rail car unit 404 is an internal end to which an articulatedconnector portion, namely male articulated connector portion 410 ismounted. Male articulated connector portion 410 is mounted in a pocketformed between the upstanding side webs, and the bottom flanges of thelongitudinally outboard extending end of stub center sill 503, and afalse flange, or web, 544 welded inside center sill 503 below the levelof shear plate 546.

A pair of side bearing arms 550 and 552 are mounted to, and extendlongitudinally outboard from, end bolster 506 to bracket malearticulated connection portion 410. Reinforcements, that is, a pair oflongitudinally extending stiffening members in the nature of steel beams554 and 556, are mounted intermediate center sill 503 and side sills 508and 510, respectively, such that they mate with end bolster 506 at thelateral station corresponding to the root of each of side bearing arms550 and 552. Beams 554 and 556 run inwardly to terminate at bolster 512.Gussets are located opposite the webs of beams 554 and 556 to provideweb continuity at the junctions with bolster 512 and end bolster 506. Itwill be noted that side bearing arms 550 and 552 has bearing surfaces560 and 562 that face downwardly to permit engagement with the upwardlyfacing bearing surfaces 490 and 492 of unit 402 when articulatedconnector portions 408 and 410 are engaged and car 400 is operated on abend.

When male portion 410 engages female portion 408, a vertical shear loadfrom unit 404 is transferred to the cantilever formed by stub sill 420,and the associated overhanging end structure 464 of unit 402. Thevertical reaction to this force is provided by truck 418 acting throughsecond main bolster 426 of unit 402. The bending moment in sill 422 atthe truck center location of truck 418 is balanced by the weight of carunit 402 lying toward truck 416.

Although end portion 502 of unit 404 does not have a truck, and althoughmale articulated connector portion 540 is not supported directly over atruck, and although side bearing arms 560 and 562 are not reacted byside bearing arm pedestals mounted on a truck, but rather by sidebearing arms 490 and 492, vertical weight tends to be carried by thefemale articulated connector portion 408 in the same manner as if itwere carried above an articulated truck. That is, from the male side ofthe connection, the load transfer may tend to appear to be unchanged.

Although rail car unit 404 is shown as a single unit end truck, having asingle internal male articulated connector portion at the unsupportedinternal end (namely end 502), and rail car unit 402 is shown as asingle unit two-truck end unit having a single internal female end,other combinations are possible. For example, as suggested by theforeshortening abridgement section of FIGS. 9 a, 9 b, 9 c and 9 d, twointernal male ends, such as end portion 502, can be assembled to yield atruckless car supported only at the permanent male articulated connectorfittings at either end of the car. Such an internal car could be used asthe middle car in the embodiment of FIG. 3 c, for example. Similarly, aninternal car with female articulated connector portions can be made byassembling two ends such as proximate end portion 412 of FIGS. 9 a and 9b. Such a car can be used as the middle car unit in a layout such asdescribed in FIG. 3 b. Thirdly, a single truck intermediate car unit canbe manufactured by combining the proximate end portion 502 of car unit404 with the proximate end portion 412 of car unit 402. In this way, allof the combinations of layout noted above can be assembled usingcombinations of the end portions shown and described in FIGS. 9 a, 9 b,9 c and 9 d. In this way the construction shown and described permitsthe manufacture of the sets and combinations of layout of articulatedrail road cars shown in FIGS. 2 a to 5 e. It will also be noted thatflat cars, or auto-rack cars, or box cars, or other types of cars can beassembled using the same type of construction as described in FIGS. 9 a,9 b, 9 c and 9 d.

Various embodiments of the invention have now been described in detail.Since changes in and or additions to the above-described embodiments maybe made without departing from the nature, spirit or scope of theinvention, the invention is not to be limited to those specificembodiments.

1. An articulated rail road freight car having releasable couplersmounted at either end thereof, said articulated rail road freight carbeing supported by a plurality of pivotally mounted rail car trucks,each of said pivotally mounted rail car trucks having spaced apartaxles, and said articulated rail road freight car having at least firstand second rail car units connected at a cantilevered articulationthrough which a vertical shear load arising from one of said first andsecond rail car units is carried to the other of said first and secondrail car units.
 2. An articulated rail road freight car comprising atleast first and second rail car units connected at a cantileveredarticulated connector through which vertical shear loads arising in saidfirst rail car unit are passed to said second rail car unit, said railroad freight car having a first end, a second end, and a releasablecoupler mounted at each of said first and second ends, said releasablecouplers being capable of interchangeable operation with other rail roadfreight cars in North American service.
 3. The articulated rail roadfreight car of claim 2 wherein said first and second rail car units eachhave at least one deck upon which vehicles can be loaded.
 4. Thearticulated rail road freight car of claim 3 further comprising at leastone member mounted to permit vehicles to be conducted between said firstand second rail car units.
 5. The articulated rail road freight car ofclaim 3 further comprising bridge plates mounted to permit vehicles tobe driven from said first rail car unit to said second rail car unit. 6.The articulated rail road freight car of claim 2 wherein said first andsecond rail car units have mutually engaging side bearing arms.
 7. Thearticulated rail road freight car of claim 6 wherein said rail road caris an auto-rack car.
 8. The articulated rail road freight car of claim 7further comprising bridge plates mounted to permit automobiles to beconducted between said first and second rail car units.
 9. Thearticulated rail road freight car of claim 7 wherein said first andsecond rail car units have mutually engaging side bearing arms.
 10. Thearticulated rail road freight car of claim 2 wherein at least one ofsaid first and second rail car units is a well car unit.
 11. Thearticulated rail road freight car of claim 2 wherein: said first railcar unit has a first end and a second end; said second rail car unit hasa first end and a second end; said second end of said first rail carunit is joined to said first end of said second rail car unit at saidarticulated connector; the second rail car unit is supported upon a pairof pivotally mounted, spaced apart, first and second two-axle rail cartrucks, each of said trucks having a truck center; said first truck ofsaid second rail car unit is located closer to said articulatedconnector than any other truck of said rail road car; and saidarticulated connector is offset from said truck center of said firsttruck.
 12. The articulated rail road freight car of claim 11 wherein:said articulated connector is a first articulated connector; saidrailroad freight car includes a third rail car unit; the third rail carunit has a first end and a second end; the second end of the second railcar unit is joined to the first end of the third rail car unit at asecond articulated connector; said second truck of said second rail carunit is located closer to said second articulated connector than anyother truck of said rail road car; and said second articulated connectoris offset from said truck center of said second truck.
 13. Thearticulated rail road freight car of claim 12 wherein said third railcar unit has a two-axle truck pivotally mounted thereunder, and saidtwo-axle truck of said third rail car unit is located closer to saidsecond end of said third rail car unit than to said first end of saidthird rail car unit.
 14. The articulated rail road freight car of claim13 wherein a releasable coupler is mounted at said second end of saidthird rail car unit.
 15. An articulated rail road freight car comprisinga three pack rail road car having a middle unit and a pair of end units,each of the end units having only one rail road car truck mountedthereto and the middle unit having two rail road car trucks pivotallymounted thereto, said middle unit being connected to at least one of theend units at a cantilevered articulation, and the two rail road trucksmounted to said middle unit, each rail road truck having a first axleand a second axle.
 16. The articulated rail road freight car of claim 15wherein each said rail road car unit has at least one deck upon whichvehicles can be loaded.
 17. The articulated rail road freight car ofclaim 16 further comprising at least one member mounted to permitvehicles to be conducted between adjacent rail road car units.
 18. Thearticulated rail road car of claim 16 further comprising bridge platesmounted to permit vehicles to be driven from each said rail road carunit to an adjacent said rail road car unit.
 19. The articulated railroad freight car of claim 15 wherein each said rail road car unit hasside bearing arms, said side bearing arms being mutually engaged withside bearing arms of another of said units.
 20. The articulated railroad freight car of claim 15 wherein each said rail road car unit is anauto-rack car.
 21. The articulated rail road freight car of claim 20further comprising bridge plates mounted to permit automobiles to beconducted from each said rail road car unit to an adjacent rail road carunit.
 22. The articulated rail road freight car of claim 20 wherein saidfirst and second rail car units have mutually engaging side bearingarms.
 23. An articulated rail road freight car having releasablecouplers mounted at either end thereof, and wherein: said articulatedrail road freight car has at least a first rail car unit, a second railcar unit, and a third rail car unit, said second rail car unit lyingbetween said first and third rail car units; said articulated rail roadcar has rail car trucks mounted to support said rail car units; saidfirst rail car unit is connected to said second rail car unit at a firstarticulation connection; a first truck of said trucks is mounted closerto said first articulation connection than is any other of said trucks,said first truck having a first axle and a second axle; said second railcar unit is connected to said third rail car unit at a secondarticulation connection; a second truck of said trucks is mounted closerto said second articulation connection than is any other of said trucks,said second truck having a first axle and a second axle; and none ofsaid rail car trucks is mounted centrally under either of said first andsecond articulation connections.
 24. The articulated rail road freightcar of claim 23 wherein said articulated rail road freight car is freeof trucks between said first and second articulation connections. 25.The articulated rail road freight car of claim 24 wherein each of saidfirst and third rail car units is supported by a spaced apart pair ofsaid rail car trucks mounted thereunder.
 26. The articulated rail roadfreight car of claim 24 wherein each of said first and third rail carunits has a cantilever member extending toward said second rail carunit, and said first and second articulation connections are mountedrespectively to said cantilever members of said first and third rail carunits.
 27. The articulated rail road freight car of claim 24 wherein: afourth rail car unit is connected to said third rail car unit at a thirdarticulation connection; said third rail car unit has a first endadjacent said second articulation connection and a second end adjacentsaid third articulation connection; said first rail car unit issupported by a pair of said rail car trucks, namely first and secondspaced apart rail car trucks mounted thereunder, none of said trucksbeing mounted centrally under said third articulation connection; and athird one of said rail car trucks is mounted under said first end ofsaid third rail car unit.
 28. The articulated rail road freight car ofclaim 24 wherein: a fourth rail car unit is connected to said first railcar unit at a third articulation connection; a fifth rail car unit isconnected to said third rail car unit at a fourth articulationconnection; said first rail car unit has a first end adjacent said firstarticulation connection and a second end adjacent said thirdarticulation connection; said third rail car unit has a first endadjacent said second articulation connection and a second end adjacentsaid fourth articulation connection; none of said rail car trucks ismounted centrally under said third articulation connection; none of saidrail car trucks is mounted centrally under said fourth articulationconnection; a first of said rail car trucks is mounted under said firstend of said first rail car unit; and a second of said rail car trucks ismounted under said first end of said third rail car unit.